Varying to much?

Hello. As I read in books,forums,sites etc I understand that varying is VERY good. Ok. But, how do I have to vary? I mean...can I make 1st day pull-ups in piramid mode and 2nd day in ladder mode? Can I make 1st day wide push-ups and 2nd diamond push-ups? When vary comes on, how much time do I have to work on one specific time and then get to another type of exercise?

Vary as much as you like, if you fancy doing one day pull-ups only go for it... if you want to alternate wide and diamond press-ups everyday, that's all good .

As to how much time per exercise... it completely depends on what you want to do, you might spend an hour or 2 doing pull-ups on the day that you decide to do just pull-ups, another day you might only spend 15 mins including rest .